Scientists say an Asian elephant at a South Korean zoo can imitate human speech, saying five Korean words that are readily understood by people who speak the language.

The male elephant, named Koshik, invented an unusual method of sound production that involves putting his trunk in his mouth and manipulating his vocal tract.

"This is not the kind of sound that Asian elephants normally make, and it's a dead-on match of the speech of his trainers," says Tecumseh Fitch of the University of Vienna in Austria.

Many birds are excellent vocal mimics, but this isn't common among mammals.

Humans can do it, of course — but our closest primate relatives can't. Dolphins, whales and seals are known to imitate sounds. Dolphins can mimic weird computer-generated noises, for example, and one seal named Hoover famously learned to say phrases like "hello there" after being raised by a Maine fisherman.

And scientists already knew that elephants have some ability to mimic what they hear. In 2005, researchers reported on a female African elephant that made truck sounds and a male African elephant that learned to chirp like the Asian elephants he lived with at a zoo.

What Koshik can do goes way beyond what's been heard from elephants before. Videos show him putting his trunk in his mouth and saying "annyong" ("hello"), "anja" ("sit down"), "aniya" ("no"), "nuo" ("lie down") and "choah" ("good") — all words he presumably picked up from his trainers.

Scientists saw these videos on You Tube and didn't know what to think. "There had been always the question, 'Is this true, or is it a fake?' No one really believed it," says Angela Stoeger, also at the University of Vienna. She and her colleagues went to check it out.

Their study, in the journal Current Biology, shows that Koshik is the real deal. The researchers compared his utterances with normal Asian elephant sounds and showed that he clearly was not just making some elephant noise that was being interpreted by onlookers as human speech.

"There is no way this is just some sort of accidental thing, that the elephant was making normal elephant sounds and somehow got rewarded for doing it and then people started saying, 'Oh, he's a talking elephant,' " says Fitch. "That's what I think makes it really convincing that this is speech mimicry."

What's more, the researchers asked native Korean speakers to listen to the sounds made by Koshik and transcribe what they heard. While most listeners agreed on the vowel sounds, there was some disagreement on what consonants he was saying. "His consonants are kind of blurry in the same way that mine might be if I'd had a half a bottle of Jack Daniel's or something," says Fitch.

What most struck the researchers is that Koshik was apparently so driven to imitate sounds that he invented the method of putting his trunk in his mouth and moving it around. They believe that he may have done this to bond with his trainers, as he was deprived of elephant companionship during a critical period of his childhood and spent years with humans as his only social contact.

Researchers now want to know exactly what he is doing with his trunk that produces the effect. And Stoeger says this raises the question of whether elephants in the wild also use vocal imitation for some kind of social bonding. "And now we can actually go and check whether elephants in their natural communication system will use this ability in a similar way — but not as obviously," she says.

Stoeger also says studying the rare examples of vocal learning in the world of mammals could help shed light on why this ability evolved in humans. "There are such different species that share this ability, and why would that have developed?" she asks, noting that the question is important because this vocal imitation is so essential for things like language and music.

Copyright 2014 NPR. To see more, visit http://www.npr.org/.

Transcript

RENEE MONTAGNE, HOST:

Many birds, like parrots, are talented vocal mimics, but mammals? Not so much. That's why scientists were stunned when they learned about the vocal talents of an elephant in South Korea. NPR's Nell Greenfieldboyce reports that this elephant can distinctly say five different Korean words.

NELL GREENFIELDBOYCE, BYLINE: The Asian elephant is named Koshik, and he lives at the Everland Zoo in South Korea, where he's famous. In this recording, you can hear Koshik loudly bellowing the Korean word for good, over and over. Much softer, you hear his Korean trainer saying the words for good, good, hello.

(SOUNDBITE OF ELEPHANT)

GREENFIELDBOYCE: A researcher named Tecumseh Fitch saw a video of Koshik at a science conference and thought: This can't be true.

TECUMSEH FITCH: At the time I thought it was a hoax. I thought it was a joke and I'd heard that it was on YouTube and stuff.

GREENFIELDBOYCE: Fitch studies vocal learning in animals at the University of Vienna in Austria. He says most mammals can't mimic sounds. Humans can - but not other primates, like chimps and gorillas. Marine mammals are good at it. Dolphins can mimic computer-generated noises. One beluga whale made unusual sounds that had the rhythm and cadence of human speech.

And one seal named Hoover, who was raised by a Maine fisherman, even learned to say phrases. Here's Hoover making some noises that include hello there.

(SOUNDBITE OF SEAL)

HOOVER: Hello there. Hey, hey, hey. Hey.

GREENFIELDBOYCE: Scientists did already know of a few elephants that could mimic sounds. For example, there's one African elephant who likes to make truck noises. But an elephant that can speak Korean? Fitch suggested that some colleagues go check Koshik out, scientifically. They made a bunch of recordings. Here's the Korean trainer saying the word for hello, and then Koshik saying it.

(SOUNDBITE OF RECORDING)

UNIDENTIFIED MAN: Anyong.

KOSHIK: Anyong.

UNIDENTIFIED MAN: Anyong.

KOSHIK: Anyong.

FITCH: This is not the kind of sound that Asian elephants normally make, and it's a dead on match of the speech of his trainers.

GREENFIELDBOYCE: In the journal Current Biology, Fitch and his colleagues report that Koshik is the real deal, unlike a lot of other talking animal claims.

FITCH: Well, if you look on YouTube for talking animals, you'll find all these things where you've got a dog that's kind of going rawr-rawr-rawr-rawr-rawr. And then people say he's saying I love you. And, you know, if you listen you can kind of hear rawr-rawr-rawr, but all it is is just a dog kind of growling and moving his mouth. It's a normal dog vocalization.

GREENFIELDBOYCE: What Koshik is doing is not normal. To imitate human speech, the elephant had to invent a new way of making sounds. He puts his trunk into his mouth and somehow manipulates his vocal tract. Fitch says the elephant must have been incredibly driven to do this. He thinks the animal wanted to bond with his human companions.

FITCH: What's interesting about Koshik is that he was basically deprived of contact with elephants in a crucial period of his childhood. The only company he had were his human trainers and his human keepers.

GREENFIELDBOYCE: And the words he learned are the ones he often heard them say: the Korean words for hello, sit down, lie down, no, and good. Fitch says by learning more about Koshik and other animals that imitate sounds, scientists might start to understand why humans evolved to do this so well.

FITCH: This is not just a circus trick. This is not just a fun thing that animals do. It actually really gets at something that's very unusual and interesting about our own species.